agrotecnologia

Abstrato

Evaluation of Bradyrhizobium strain rates for growth, nodulation and yield of Soybean (Glycine max L.) at Seka District, Jimma Zone, Southwestern Ethiopia

Habetamu Getinet*, Obsa Atinafu

Rhizobial strains have contributed to enhance nitrogen fixation thereby soil fertility and yield of legumes crops when they are inoculated to seeds with sufficient quantity. Therefore a field experiment was conducted at Jimma Agricultural Research Center (JARC) to determine appropriate rate of Bradyrhizobium japonicum strains on nodulation and seed yield of soybean in south western Ethiopia during 2017/18 main cropping season. Six rates of strains (125, 250, 500, 625, 750 and 900 gm ha^-1), one control (UN inoculated) and one 18 kgha^-1 N were used. The experiment was designed in a Randomized Complete Block Design (RCBD) replicated three times giving a total of 24 plots. Nodulation parameters (nodule number and dry nodule weight,) was highly (P<0.01) affected due to inoculation and plant height, seed number plant-1, seed yield and above ground biomass was significantly (P<0.05) affected while pod height, pod number and hundred seed weight showed non-significant difference (P>0.05) due to bio inoculation of varying Bradyrhizobium strains. Accordingly, the highest seed yield (2027.78 kg ha^-1) was obtained from control (inoculated) plots corresponding 7.40% yield advantages compared with the minimum strain rate which was 1877.78 kg ha^-1. The results clearly suggested that proper application of effective strains along with optimum rate affect nodulation and yield attributes of soybean.